<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>无标题文档</title>
<style>
        #father{
		   width:700px;
		   margin:0 auto;
		   }
     #d001{
		 width:700px;
		 height:200px;
		 background-color:#F00;
		 margin-bottom:10px;
		 }
		 #d002{
		 width:500px;
		 height:200px;
		 background-color:blue;
		 float:left;
		 margin-bottom:10px;
		 }
		 #d003{
		 width:190px;
		 height:200px;
		 background-color:green;
		 float:left;
		 margin-bottom:10px;
		 margin-left:10px;
		 		 }#d004{
		 width:700px;
		 height:200px;
		 background-color:pink;
		 clear:both;
		 }
</style>
</head>
<body>
<div id="father">
<div id="d001">我不动</div>
<div id="d002">我往左边浮动</div>
<div id="d003">我往左边浮动</div>
<div id="d004">第四个</div>
</div>


</body>
</html>
